scholarly journals Oxidation of soot over supported RuRe nanoparticles prepared by the microwave-polyol method

2021 ◽  
Author(s):  
Katarzyna Adamska ◽  
Szymon Smykała ◽  
Sebastian Zieliński ◽  
Damian Szymański ◽  
Agnieszka Hojeńska ◽  
...  
Keyword(s):  
Bimetallic Nanoparticles ◽  
Catalytic Properties ◽  
Soot Oxidation ◽  
Catalytic Performance ◽  
Polyol Method ◽  
Nano Catalyst ◽  
The Stability ◽  
Nano Catalysts ◽  
The Relationship ◽  
Very High

AbstractThe oxidation of soot over RuRe bimetallic nanoparticles (NPs) supported on γ-Al2O3 has been investigated. The catalysts were synthesized by a microwave-polyol method and characterized by ICP, BET, TEM, STEM-EDS, XRD and XPS techniques. The study revealed that the proper choice of the Re loading (0.4–2.0 wt%) is crucial for the catalytic behavior of the 2% Ru–Re/Al2O3 nano-catalysts.The best catalytic properties, in terms of overall activity and stability, were observed for the 2%Ru-0.8%Re/γ-Al2O3 nano-catalyst. The stability of all bimetallic 2% Ru–Re nano-catalysts in catalytic soot oxidation in the presence of oxygen is very high in contrast to the 2% Ru/γ-Al2O3 sample. The presence of rhenium in the catalytic system hinder the formation of large RuO2 agglomerates leading to a better dispersion of active ruthenium phase and a better catalytic performance. The relationship between the catalytic activity of Ru–Re/γ-Al2O3 and the synergetic roles of Ru and Re is discussed.

Synthesis of Dimethyl Carbonate from Ethylene Carbonate and Methanol Over Nano-Catalysts Supported on CeO2–MgO

2015 ◽  
Vol 15 (10) ◽  
pp. 8330-8335 ◽  
Author(s):  
Jin Oh Jun ◽  
Joongwon Lee ◽  
Ki Hyuk Kang ◽  
In Kyu Song
Keyword(s):  
Dimethyl Carbonate ◽  
Ethylene Carbonate ◽  
Earth Metal ◽  
Catalytic Performance ◽  
Precipitation Method ◽  
Reaction Yield ◽  
Incipient Wetness Impregnation ◽  
Impregnation Method ◽  
Nano Catalyst ◽  
Nano Catalysts

A series of CeO2(X)–MgO(1−X) (X = 0, 0.25, 0.5, 0.75, and 1.0) nano-catalysts were prepared by a co-precipitation method for use in the synthesis of dimethyl carbonate from ethylene carbonate and methanol. Among the CeO2(X)–MgO(1−X) catalysts, CeO2(0.25)–MgO(0.75) nano-catalyst showed the best catalytic performance. Alkali and alkaline earth metal oxides (MO = Li2O, K2O, Cs2O, SrO, and BaO) were then supported on CeO2(0.25)–MgO(0.75) by an incipient wetness impregnation method with an aim of improving the catalytic performance of CeO2(0.25)–MgO(0.75). Basicity of the catalysts was determined by CO2-TPD experiments in order to elucidate the effect of basicity on the catalytic performance. The correlation between catalytic performance and basicity showed that basicity played an important role in the reaction. Yield for dimethyl carbonate increased with increasing basicity of the catalysts. Among the catalysts tested, Li2O/CeO2(0.25)–MgO(0.75) nano-catalyst with the largest basicity showed the best catalytic performance in the synthesis of dimethyl carbonate.

scholarly journals Synthesis, characterization and catalytic activity of partially substituted La1−xBaxCoO3 (x ≥ 0.1 ≤ 0.4) nano catalysts for potential soot oxidation in diesel particulate filters in diesel engines

2020 ◽  
Vol 11 (1) ◽  
pp. 52-57
Author(s):  
Kayode Akinlolu ◽  
Bamgboye Omolara ◽  
Tripathi Shailendra ◽  
Akinsiku Abimbola ◽  
Ogunniran Kehinde
Keyword(s):  
Surface Area ◽  
Inductively Coupled Plasma ◽  
Research Study ◽  
Sol Gel ◽  
Soot Oxidation ◽  
Atomic Emission ◽  
Catalytic Performance ◽  
Inductively Coupled ◽  
Perovskite Catalysts ◽  
Nano Catalysts

AbstractThe sol gel method was used in preparing a series of A site partially substituted La1−xBaxCoO3 (x ≥ 0.1 ≤ 0.4) perovskite catalysts coded LBC1, 2, 3, and 4 and their potential as catalysts for soot oxidation were evaluated. The Brunauer–Emmett–Teller (BET), Inductively Coupled Plasma Atomic Emission Spectroscopy (ICPAES), Thermogravimetric/Differential Thermal Analysis (TGA/DTG), X-ray analysis (XRD) were used in characterizing the prepared perovskite catalyst. The result shows that at (x≥ 0.2 ≤ 0.4), there was an increase in surface area when we compare it with that of x = 0. The increase in surface area helps in increasing the catalytic performance of the catalyst. Also, when evaluating the catalytic performance of the synthesized catalysts, it was observed that doping the perovskite catalysts helped in the general improvement of the catalytic performance for soot oxidation. The best performance in this research study with a T50 of 484 °C was observed at x = 0.2 catalyst (LBC2). This shows that the non-noble perovskite catalysts prepared in this research study has the potential to replace the noble metal based catalysts used presently in the diesel automotive industry.

scholarly journals Noble Metal Nanoparticles Incorporated Siliceous TUD-1 Mesoporous Nano-Catalyst for Low-Temperature Oxidation of Carbon Monoxide

Nanomaterials ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 1067 ◽  
Author(s):  
Badria M. Al-Shehri ◽  
Mohd Shkir ◽  
A. S. Khder ◽  
Ajeet Kaushik ◽  
Mohamed S. Hamdy
Keyword(s):  
Carbon Monoxide ◽  
Metal Nanoparticles ◽  
Noble Metal ◽  
Catalytic Performance ◽  
Noble Metal Nanoparticles ◽  
Low Temperature Oxidation ◽  
Temperature Oxidation ◽  
Nano Catalyst ◽  
Nano Catalysts ◽  
Oxidation Of Carbon Monoxide

This report, for the first time, demonstrated the low-temperature oxidation of carbon monoxide (CO) using nano-catalysts consisting of noble metal nanoparticles incorporated in TUD-1 mesoporous silica nano-structures synthesized via a one-pot surfactant-free sol–gel synthesis methodology. Herein, we investigated a nano-catalyst, represented as M-TUD-1 (M = Rh, Pd, Pt and Au), which was prepared using a constant Si/M ratio of 100. The outcome of the analytical studies confirmed the formation of a nano-catalyst ranging from 5 to 10 nm wherein noble metal nanoparticles were distributed uniformly onto the mesopores of TUD-1. The catalytic performance of M-TUD-1 catalysts was examined in the environmentally impacted CO oxidation reaction to CO2. The catalytic performance of Au-TUD-1 benchmarked other M-TUD-1 catalysts and a total conversion of CO was obtained at 303 K. The activity of the other nano-catalysts was obtained as Pt-TUD-1 > Pd-TUD-1 > Rh-TUD-1, with a total CO conversion at temperatures of 308, 328 and 348 K, respectively. The Au-TUD-1 exhibited a high stability and reusability as indicated by the observed high activity after ten continuous runs without any treatment. The outcomes of this research suggested that M-TUD-1 are promising nano-catalysts for the removal of the toxic CO gas and can also potentially be useful to protect the environment where a long-life time, cost-effectiveness and industrial scaling-up are the key approaches.

scholarly journals Synthesis and Characterization of A-Site Doped Lamno3 Nano Catalysts and its Application for Soot Oxidation

2019 ◽  
Vol 35 (3) ◽  
pp. 927-937
Author(s):  
Kayode Akinlolu ◽  
Abimbola Adebisi ◽  
Bamgboye Omolara ◽  
Ogunniran Kehinde
Keyword(s):  
Citric Acid ◽  
Surface Area ◽  
Preparation Method ◽  
Sol Gel ◽  
Soot Oxidation ◽  
Catalytic Performance ◽  
Synthesis And Characterization ◽  
Nano Catalysts ◽  
A Site

A series of barium doped LaMnO3 perovskite nano catalysts were synthesized using the citric acid sol gel method. The prepared nano catalysts were characterized using the various characterization techniques such as XRD, ICPAES, FTIR, SEM, HRTEM, TPR and BET. The Xrd results showed the purity of the prepared catalyst as no segregated phases were observed and also confirming the crystallinity of the prepared catalyst. The surface area achieved in this experiment presented one of the highest reported in literature. The doping of the perovskite catalysts helps in increasing the surface area. The ICPAES results shows the efficiency of the preparation method adopted. The catalytic evaluation shows that upon introduction of Ba into the perovskite structure, the catalytic performance of the catalyst were greatly increased with LBM3 giving the lowest T50 at 550°C

Direct Dehydrogenation of n-Butane Over Pt/Sn/Zn/γ-Al2O3 Nano-Catalyst: Effect of Zn Content

2015 ◽  
Vol 15 (10) ◽  
pp. 8318-8323
Author(s):  
Hyun Seo ◽  
Jong Kwon Lee ◽  
Ung Gi Hong ◽  
Gle Park ◽  
Yeonshick Yoo ◽  
...  
Keyword(s):  
Surface Area ◽  
Zinc Content ◽  
Catalytic Performance ◽  
Impregnation Method ◽  
Support Interaction ◽  
Nano Catalyst ◽  
Metal Support Interaction ◽  
Zn Content ◽  
Metal Support ◽  
Nano Catalysts

A series of Pt/Sn/XZn/γ-Al2O3 nano-catalysts with different Zn content (X = 0, 0.25, 0.5, 0.75, and 1.0 wt%) were prepared by a sequential impregnation method. They were applied to the direct dehydrogenation of n-butane to n-butene and 1,3-butadiene. The effect of zinc content of Pt/Sn/XZn/γ-Al2O3 nano-catalysts on their physicochemical properties and catalytic activities in the direct dehydrogenation of n-butane was investigated. The catalytic performance of Pt/Sn/XZn/γ-Al2O3 nano-catalysts strongly depended on zinc content. Among the catalysts tested, Pt/Sn/0.5Zn/γ-Al2O3 nano-catalyst showed the best catalytic performance in terms of yield for total dehydrogenation products (TDP, n-butene and 1,3-butadiene). TPR (temperature-programmed reduction) and H2-chemisorption experiments were carried out to measure metal-support interaction and Pt surface area of the catalysts. Experimental results revealed that metal-support interaction and Pt surface area of the catalysts were closely related to the catalytic performance. Yield for TDP increased with increasing metal-support interaction and Pt surface area of the catalysts.

Influence of nanoscale structuralisation on the catalytic performance of ZIF-8: a cautionary surface catalysis study

CrystEngComm ◽  
2018 ◽  
Vol 20 (34) ◽  
pp. 4926-4934 ◽  
Author(s):  
Oliver M. Linder-Patton ◽  
Thomas J. de Prinse ◽  
Shuhei Furukawa ◽  
Stephen G. Bell ◽  
Kenji Sumida ◽  
...  
Keyword(s):  
Catalytic Properties ◽  
Catalytic Performance ◽  
Zeolitic Imidazolate Framework ◽  
Surface Catalysis ◽  
The Stability

Nanoscale structuralisation is demonstrated to influence the stability and catalytic properties of zeolitic imidazolate framework-8.

Psychiatric Comorbidity in Eating Disorders Not Otherwise Specified (EDNOS)

2009 ◽  
Vol 24 (S1) ◽  
pp. 1-1
Author(s):  
G. Milos
Keyword(s):  
Eating Disorders ◽  
Total Sample ◽  
Structured Interview ◽  
Not Otherwise Specified ◽  
Axis I ◽  
Dsm Iv ◽  
One Year ◽  
The Stability ◽  
The Relationship ◽  
Very High

This study aimed to analyse the course of eating disorders (ED) over thirty months emphasizing comorbidity and stability of the ED diagnoses. Particularly attention was given to the eating disorders not otherwise specified (EDNOS) subjects in comparison with anorexia nervosa (AN) and bulimia nervosa (BN) patients.192 women with a DSM IV eating disorder diagnosis - 55 AN, 108 BN, 29 EDNOS - was assessed with the structured interview (SCID I) at the baseline, one year and thirty months after the first assessment.83.3% of the total sample had in addition to the ED diagnosis one or more lifetime axis I diagnoses. We found no significant differences between the most common axis diagnoses - anxiety and affective disorders, or dependence disorders - in the three diagnostic groups, excepted for social phobia, in fact this disorder was significantly often present in AN. The distribution of the lifetime suicidal attempt was very similar in the three diagnostic groups.The stability of the ED diagnoses was low, but EDNOS was the most instable ED diagnosis with a tendency to remission.The axis I comorbidity of ED was very high, and the EDNOS subjects showed a very similar axis I comorbidity compared with subjects with AN and BN. The stability of the ED diagnoses was low and the EDNOS group showed the highest ED diagnosis instability and tendency to remission. The relationship between axis I comorbidity, and ED instability is unclear, further studies in these fields are needed.

Platinum-Tin Nano-Catalysts Supported on Alumina for Direct Dehydrogenation of n-Butane

2015 ◽  
Vol 15 (10) ◽  
pp. 8305-8310 ◽  
Author(s):  
Jong Kwon Lee ◽  
Hyun Seo ◽  
Ung Gi Hong ◽  
Gle Park ◽  
Yeonshick Yoo ◽  
...  
Keyword(s):  
Surface Area ◽  
Catalytic Performance ◽  
Precipitation Method ◽  
Hydrogen Chemisorption ◽  
Impregnation Method ◽  
Platinum Surface ◽  
Catalytic Activities ◽  
Nano Catalyst ◽  
Basic Solutions ◽  
Nano Catalysts

Al2O3 supports were prepared by a precipitation method using various basic solutions (NaOH, KOH, NH4OH, and Na2CO3) as precipitation agents, and Pt/Sn/Al2O3 nano-catalysts were then prepared by a sequential impregnation method. The prepared catalysts were applied to the direct dehydrogenation of n-butane to n-butenes and 1,3-butadiene. The effect of precipitation agents on the physicochemical properties and catalytic activities of Pt/Sn/Al2O3 nano-catalysts in the direct dehydrogenation of n-butane was investigated. Catalytic performance of Pt/Sn/Al2O3 nanocatalysts decreased in order of Pt/Sn/Al2O3 (NaOH) > Pt/Sn/Al2O3 (KOH) > Pt/Sn/Al2O3 (NH4OH) > Pt/Sn/Al2O3 (Na2CO3). Among the catalysts tested, Pt/Sn/Al2O3 (NaOH) nano-catalyst showed the best catalytic performance in terms of yield for total dehydrogenation products (TDP, n-butenes and 1,3-butadiene). Hydrogen chemisorption experiments revealed that platinum surface area of the catalyst was closely related to the catalytic performance. Yield for TDP increased with increasing platinum surface area of the catalyst.

An Experimental Investigation on Thermal Conductivity and Viscosity of Graphene doped CNTs /TiO2 Nanofluid

2020 ◽  
Vol 17 (3) ◽  
Author(s):  
A.M. Zetty Akhtar ◽  
M.M. Rahman ◽  
K. Kadirgama ◽  
M.A. Maleque
Keyword(s):  
Thermal Conductivity ◽  
Zeta Potential ◽  
Base Fluid ◽  
Minimum Quantity Lubrication ◽  
Cutting Fluid ◽  
Cutting Zone ◽  
Observation Method ◽  
The Stability ◽  
The Relationship ◽  
Zeta Potential Analysis

This paper presents the findings of the stability, thermal conductivity and viscosity of CNTs (doped with 10 wt% graphene)- TiO2 hybrid nanofluids under various concentrations. While the usage of cutting fluid in machining operation is necessary for removing the heat generated at the cutting zone, the excessive use of it could lead to environmental and health issue to the operators. Therefore, the minimum quantity lubrication (MQL) to replace the conventional flooding was introduced. The MQL method minimises the usage of cutting fluid as a step to achieve a cleaner environment and sustainable machining. However, the low thermal conductivity of the base fluid in the MQL system caused the insufficient removal of heat generated in the cutting zone. Addition of nanoparticles to the base fluid was then introduced to enhance the performance of cutting fluids. The ethylene glycol used as the base fluid, titanium dioxide (TiO2) and carbon nanotubes (CNTs) nanoparticle mixed to produce nanofluids with concentrations of 0.02 to 0.1 wt.% with an interval of 0.02 wt%. The mixing ratio of TiO2: CNTs was 90:10 and ratio of SDBS (surfactant): CNTs was 10:1. The stability of nanofluid checked using observation method and zeta potential analysis. The thermal conductivity and viscosity of suspension were measured at a temperature range between 30˚C to 70˚C (with increment of 10˚C) to determine the relationship between concentration and temperature on nanofluid’s thermal physical properties. Based on the results obtained, zeta potential value for nanofluid range from -50 to -70 mV indicates a good stability of the suspension. Thermal conductivity of nanofluid increases as an increase of temperature and enhancement ratio is within the range of 1.51 to 4.53 compared to the base fluid. Meanwhile, the viscosity of nanofluid shows decrements with an increase of the temperature remarks significant advantage in pumping power. The developed nanofluid in this study found to be stable with enhanced thermal conductivity and decrease in viscosity, which at once make it possible to be use as nanolubricant in machining operation.

TAFSIR AYAT-AYAT ZAKAT SEBAGAI PENGUAT KONSEP FILANTROPI EKONOMI KEUMMATAN (Tafsir Verses Of Zakat As The Booster Of Public Economic Philanthropy Concept)

2019 ◽  
Vol 3 (2) ◽  
pp. 117-137
Author(s):  
Mustaqim Makki
Keyword(s):  
Economic Crisis ◽  
Human Life ◽  
Minimum Level ◽  
Relationship With God ◽  
Public Economic ◽  
Close Relationship ◽  
Vertical Relationship ◽  
The Relationship ◽  
Very High ◽  
Functional Content

Zakat merupakan salah satu sendi pokok ajaran Islam. Urgensi zakat yang merupakan anjuran agama Islam untuk menunaikan zakat dan memberikannya kepada yang berhak dengan ketentuan mencapai nishabnya, (kadar minimum harta tertentu) mempunyai nilai sangat signifikan dalam kehidupan manusia. Seorang insan yang sarat akan segala permasalahan pada fitrahnya menuntut untuk selalu berinteraksi kepada sesama, baik berupa materi maupun non materi. Zakat merupakan maliyah ijtima’iyyah yang mengandung nilai-nilai filantropi yang sangat tinggi, karena ketika mengaplikasikan kewajiban zakat kita telah membantu sesama serta mengurangi kesenjangan yang disebabkan beberapa sifat manusia diantaranya adalah sifat kikir, dengki dan iri hati. Menguatnya kembali harapan banyak kalangan terhadap implementasi filantropi Islam, baik dalam bentuk zakat, infak, sedekah, dan wakaf, memiliki keterkaitan erat dengan kondisi bangsa yang belum sepenuhnya bangkit dari keterpurukan sebagai dampak dari krisis ekonomi yang berkepanjangan. Kondisi ini berakibat kesenjangan penguasaan perekonomian antar warga negara menjadi kian lebar. Pada saat itulah, ziswaf (zakat, infak, sedekah, dan wakaf) kembali dilirik dan diharapkan menjadi alternatif solusi terhadap problem kemiskinan umat. Manusia sebagai khalifah fil ardh dalam Al Qurán menekankan muatan fungsional yang harus diemban oleh manusia dalam melaksanakan tugas-tugas kesejarahan dalam kehidupannya di muka bumi. Kaitan dengan konsep tersebut, ada dua fungsi manusia. Pertama: Manusia sebagai hamba (ábid), dituntut untuk sukses menjalin hubungan secara vertikal dalam hal ini hubungannya dengan ketuhanan (Teologis). Kedua adalah manusia sebagai khalifah, dituntut untuk sukses menjalin hubungan secara horizontal dalam hal ini hubungan terhadap manusia.Kata kunci: tafsir ayat zakat, filantropi, ekonomi keummatanAbstract:Zakat is one of the main points of Islamic teachings. The urgency of zakat which is suggested by Islam to fulfill and give it to those who are referred to with the provisions to reach their nishab, (minimum level of certain assets) has a very significant value in human life. A person who is full of all problems in his/her natural demands will always get interaction with other people, either material or non-material. Zakat is maliyah ijtima’iyyah which contains very high philanthropic values, because when applying the obligation of zakat we have helped others and reduced the gaps caused by some human traits including miser, jealousy and envy. The reinforcement of the expectations (estimation) from any levels on the implementation of Islamic philanthropy, which in the form of zakat, donation, alms and endowments, has a close relationship with the condition of the country that has not fully risen from bad economic adversity due to economic crisis. This condition causes a widening of the economic mastery among the citizens. At that moment, ziswaf (zakat, infaq, alms, and waqf) was again given a serious attentition and expected to be an alternative solution to the problem of poverty among citizens. Humans as khalifah fil ardh in the Qur'an emphasize the functional content that must be carried by humans in carrying out historical tasks in their lives on earth. In accordance with this concept, there are two human functions. First: Humans as servants (ábid), are required to succeed in establishing a vertical relationship in this case the relationship with God (Theological). Second, humans as caliphs, are required to succeed in establishing horizontal relationships in this case the relationship to humans.

Sign in / Sign up

Export Citation Format

Share Document